Duplicating apparatus



24, 1942- w. E. DENISON DUPLICATING APPARATUS Filed Nov. 4, 1940 4 Sheets-Sheet l INVENTOR. Cl/z'ZZz'am EDenz'son yak/45%,Wfiyfi4Q/ca Feb. 24, 1942. w, E, DENISON DUPLICATING APPARATUS Filed Nov. 4, 1940 4 Sheets-Sheet 2 J5 III/II/IIIIIIIII INVENTOR. CUZ'ZZL'Qm E0672 z'son.

Feb. 24, 1942. w. E. DENISON DUPLICATING APPARATUS 4 Sheets-Sheet 3 Filed Nov. 4, 1940 INVENTOR. E1367? iaon 1942- w. E. DENISON DUPLICATING APPARATUS Filed NOV. 4, 1940 4 Sheets-Sheet 4 I INVENTQR. CULZZzamEDcn won.

,mlzwn, 72' i 7 WM 3 Patented Feb. 24, 1942 DUPLICATING APPARATUS William E. Denison, Chicago, Ill., assignor to Ditto, Incorporated, Chicago, 111., a corporation of West Virginia Application November 4, 1940, Serial No. 364,104 (01. 101-132) Claims.

This invention relates to a duplicating apparatus of the type in which a rotatably mounted segmental drum carries a gelatin pad provided with form subject matter in reverse for transfer to a series of copy sheets pressed one at a time against the pad as the drum revolves, and

it is the object of the invention to provide a new and improved form and arrangement of parts by which improved results are obtained in the operation of the mechanism.

In the improved apparatus, a novel arrangement of mounting means is provided for the combination platen and sheet forwarding roller whereby the roller may be readily and easily adjusted to changed position with respect to; the leading edge of the segmental drum. It is import-ant that the platen roller shall exert a substantial pressure against the drum and for assuring this effect the parts are arranged so that the platen roller is displaced outwardly through an appreciable distance upon engagement with the leading edge of the drum. It is also important, however, that the: blow ofthe' platen roller on the drum and on the gelatin pad at the engagement of these parts 1 shall not be heavy enough to cause the platen roller to rebound out of engagement with the drum or to bruise or strain the fabric of thepad. An improved arrangement of the mounting means is accordingly employed for the platen roller so as to allow adjustment of the position of the roller from time to time as may be necessary or desirable.

' mental drum engages the platen roller such roller there being an ample margin portion of the copy sheet ahead of the leading edge of the segmental drum at the time when the sheet is pressed forwardly against the gelatin pad by the pressure of the" platen roller on the sheet. When the segis moved outwardly and upwardly out of engage ment with the cooperating forwarding roller, the copy sheet being thereafter drawn forwardly by its engagement with the gelatin pad onthe drum independently of any further action of Another feature of the invention is the pro- I vision of an improved drive for the sheet forwarding means comprising the platen roller and the cooperating forwarding roller. In this improved construction, the platen roller and its cooperating forwarding roller are stationary for a portionof each revolution of the segmental drum so as to permit a copy sheet to be fed into the bite of said rollers and to be positioned thereby while stationary, such feed of the sheet to the rollers taking place after the trailing edge of the segmental drum face passes the platen and before the drum again resumes engagement with the platen. Means is providedcomprising africtional driving wheel rotatably mounted in position to engage a serrated plate carried by the drum for frictionally setting the driving wheel into rotation shortly before the leadinge'dge of the segmental drum face comes into engagement with the platen roller, such driving wheel being operatively connected with the auxiliary forwarding roller for rotating it, and such auxiliary forwarding roller being adapted frictionally to drive the platen roller which stands at that time in pressure relationship thereto. The two cooperating rollers move the copy sheet forwardly to a point at which its leading end projects inwardly beyond the platen roller so as to insure said cooperating forwarding rollers. Through out the forward movement of the copy sheet with the drum, the sheet is pressed against the drum by the platen roller for effecting the desired transfer of the ink from the gelatin pad to the copy sheet. a By the use of a short frictional driving wheel for effecting the initial drive of the forwardin rollers, the desired amount of slippage may be readily brought about for permitting the rollers to be brought gradually and easily up to speed without any substantial shock or blow on the parts, means being provided for adjusting the pressure of said frictional. driving wheel against the serrated plate so as to control the extent of effective movement of the copy sheet by the cooperating forward rollers I and. thus. to regulate the size of the free margin of the copy sheet.

In the improved arrangement comprising. the invention, novel means is provided for'insuring that the gelatin pad shall be attached to. the drum at the normal position without any skewing of the pad by which there might be an uneven application of pressure on the pad for holding it on'the drum. This means comprises a see rise of lugs arranged lengthwise of the drum adapted by preliminary engagement with suit able openings. in the leading edge of the gelatin padto make it easy to adjust the pad to working position and to make it easy to detect any failure on the part ofv the operatorto get the pad to thedesired position. In the arrangement shown, the lugs are formed from sheet metal comprising fingers projecting from the edge of a sheet metal strip and bent into angular position so as to be readily engageable in the openings in. the pad. The lugs also function to prevent the leading edge of a copy sheet from being folded down tightly against the leading edge of the segmental drum, serving thus to expedite the engagement of the stripping means with such leading edge of the copy sheet.

The invention comprises further improved means for controlling the stripping mechanism.

In the preferred type of the machine inwhich this invention is embodied, a roller is provided, mounted so as to be movable inwardly and out wardly toward and from the center of theduplieating drum, adapted on the outward movement of the roller to engage the leading edge portion of a copy sheet on the drum for pressing such leading edgeof the sheet outwardly against a constantly rotating roller for drawing the copy sheet out of engagement with the gelatin pad, the roller being moved outwardly by a cam and inwardly by a spring. The invention comprises an improved arrangement of the means for applying pressure on the roller from the. cam for movement outwardly and from the spring for movement inwardly without any lost motion effect at any point, so as to keep the roller constantly under full control and so as to avoid any tendency for any of the parts to move idly. The arrangement is designed so as to be adjustable for avoiding any tendency that the spring shall approach closely to the line of centers defined by the connection of the spring to the frame and the pivotal axis of the part to which the spring is connected, assurance being provided thus that the spring shall be effective for moving the roller inwardly to the full limit of its movement as permitted by the cam.

It is another object of the invention to improve mechanisms of this type in sundry details hereinafter pointed out. The preferred means by which the several objects have been attained are illustrated in the accompanying drawings, in which Fig. 1 is a longitudinal vertical sectional View taken just inside of the frame standard at the near side of the machine;

Fig. 2 is a transverse vertical sectional View taken through the drum and the adjacent cooperating parts;

Fig. 3 is a vertical sectional view taken at the line 3-3 of Fig. 2 but with the drum removed;

Fig. 4 is a horizontal sectional view taken at the line 44 of Fig. 1;

Figs. 5 and 6 are vertical sectional views taken substantially at the line 5-5 and line 6-6 respectively of Fig. 2;

Fig. 'l is a perspective View of a bar or strip having locating lugs mounted thereon for controlling the application of a gelatin pad to the drum of the machine;

Fig. 8 is a vertical sectional view taken substantially at the line 89 of Fig. 1;

Fig. 9 is a vertical sectional view taken substantially at the line 99 of Fig. 8; and

Fig. 10 is a horizontal sectional view taken substantially at the line l-l0 of Fig. 9.

Referring now to the several figures of the drawings, in which corresponding parts are indicated'by the same reference characters, I and l6 indicate standards at opposite sides of the machine rigidly connected together by any suitable means, each of said standards being preferably in the form of an aluminum casting. Between the standards I5 and I6 a segmental drum I8 is rotatably mounted by means of a heavy shaft [9 which is rotated by means of a crank handle 20 fixedly connected therewith. A gelatin pad or band 2| of the usual type is mounted upon the segmental face portion of the drum by means of hooks 22 at one end and hooks 23 at the other end of the pad, the hooks 22 being held in position by means of a bar 24 extending longitudinally of the drum, and the hooks 23 being held in position by means of a rock shaft 25 by which the pad or band is drawn taut and secured against removal.

A pile of copy sheets 26 is supported on atray or table 21 at one side of the drum, as'shown in Fig. 2, in position to be fed one at a time to two cooperating forwarding rollers 28 and 29 by which the sheet is presented in position for operative engagement with the gelatin pad on the.

drum so as to be carried around by the drum.

- In the arrangement shown, the forwarding roller 29 is rotatably mounted between frame plates 30 carried by the standards l5 and I6, as is best shown in Fig. 3. The forwarding roller 28 is rotatably mounted in position by means of a shaft 3! which is journaled in the ends of arms 32 pivotally mounted on brackets 33 adjustably mounted on the frame plates 38 by means of ma chine screws 34 extending through slots 35 in the frame plate '39, as is best shown in Fig. 6. Each of .the arms 32 is normally drawn downwardly by means of a spring 35 secured at its upper end to the arm '32 and at its lower end to the frame plate 30, as is clearly shown in Fig. 2. The arrangement is such that in the osition of the parts as shown in Fig. 2, the inward and downward movement of the forwarding roller 28 is limited by its engagement with the forwarding roller 29. When, however, the drum I8 has been rotated a short distance in counter clockwise direction in said Fig. 2, the segmental face portion of the drum I8 engages the forwarding roller 28 so as to force it upwardly and outwardly out of engagement with the roller 29 against the action of the springs 36.

As will be appreciated from an inspection of Fig. 2, the arrangement is such that when the brackets 33 are raised with respect to the frame plates 30, the roller 28 is moved inwardly with respect to the cooperating forwarding roller 29 and with respect to the drum [8. It is thus clear that a horizontal adjustment of the roller 28 inwardly and outwardly with respect to the drum I8 may be readily effected by a vertical adjustment of the brackets 33 with respect to the frame plates 30.

For initially positioning the gelatin pad M with respect to the segmental drum IS, a series of lugs 31 are provided on the leading edge of the segmental face portion of the drum for loose engagement with openings 38 in the leading end of the gelatin pad, as is best shown in Fig. 4. The lugs 31 are formed of sheet metal extending from the edge of a strip 39 secured to the bar 24 of the drum, as is clearly shown in Fig. 2. The lugs 31 are made in the form of fingers formed integrally with the strip 39 being bent into angular form to provide the lugs 3'! which are tapered forwardly with respect to the direction of rotation of the drum l8, as indicated by the arrow in Fig. 2. When the gelatin pad is first placed in position on the drum, it is positioned generally by the engagement of the lugs 31 with the openings 38 so as to prevent any substantial misplacement of the pad on the drum. The pad is secured in tightened position on the drum, however, by the hooks 22 and 23 as above described, independently of the locating lugs 37.

Means is provided for driving the forwarding rollers 28 and 29 by power from the drum l8 when the segmental face of the drum approaches the forwarding roller 28. In the arrangement shown, this driving means comprises a bracket 48 pivotally mounted upon the frame plate 30 at the far side of the machine, as shown in Fig. 2, by means of a rivet 4|. The bracket 40 is provided with an arm 42 in spaced relation to the bracket at the upper end portion thereof so asto support a short shaft 43 rotatably in position on the bracket for supporting a hub mem her 44 provided with a driving wheel member 45" thereon. Thedriving wheel 45 is preferably made of hard rubber so as'to have an effective frictional engagement with a friction plate 46 carried by the drum l8, as best shown in Fig. i,

being serrated on its outer face, as is indicated in Fig. 2. For controlling the pressure of the driving wheel 45 against the friction plate 46, a machine screw 41 is provided for tightening the bracket 48' in position, the opening through which the screw 41 passes being in the form of a slot 48 so as to permit an adjustment of the bracket with respect to the frame plate 30.

The driving wheel 45, in the arrangement shown, is connected with the forwarding roller 29 by means ofintermeshing pinions 49 and 50 carried by the short shaft 43 and the shaft of the roller 29, as is best shown in Fig. 3. The pinion 49 is of slightly greater size than the pinion 50' so as to cause the roller 29 to move at an increased surface speed as compared with the driving wheel 45. Y

In the operation of the machine, when the drum-in its rotation in counterclockwise direction.

in Fig. Zpasses out of engagement with the roller 28, the springs 36 serve to move such roller 28 l downwardly into engagement with the forwarding roller 29. As the rotation of the drum continues, with the forwarding rollers Hand 29 standing stationary, a sheet is fed from the pile 26- into the bite of the forwarding rollers. When the friction plate 46 carried by the drum is brought into engagement with the driving wheel 45 in the continued rotation of the drum, the

driving wheel 45 is set into rotation, serving in. 5;

ing wheel 45 against the friction plate 46 on the drum is such, however, as to insure that the leading edge of the copy sheetshall extend well past the forwarding rollers 28 and 29 by the time the friction plate 66 moves out of engagement with the driving wheel 45. I

At about the same time when the-drive of the forwarding roller 29 by the driving wheel 45 is terminatecLthe leading edge of the segmental face portion of the drum I8 is brought into engagement with the forwarding roller 28 so as to force the roller upwardly and outwardly against the action of the springs: 36, with the copy sheet interposed between the edge'of the drum and the forwarding roller. In the continued rotation of the drum, the roller 26 serves as the platen or impression roller for applying the required pressure on the copy sheet against the gelatin pad for bringing about an effective transfer of ink from the pad to the copy sheet; In the operation of the roller 28 as an impression roller, the roller is, of course, driven by its frictional engagement with the copysheet and the gelatin pad, as is usual in machines of this type. With the combination platen and forwarding roller 28 in proper adjusted position with respect to the drum, the drum definitely moves the roller out of engagement with the cooperating forwarding roller 29 so as to insure that the springs 36 shall be. fully effective for pressing the platen roller are connected with links 54 for sliding movement longitudinally of the machine by means comprising slide bars 55, coiled springs 56 serving normally tohold the brackets moved to the p in Fig. 1.

limit of their motion toward the right, as shown The links 54' are actuated for moving the brackets 53 and the rollers 5| by arms or levers 5'! swingingly mounted on a cross shaft .58 mounted between the standards 15 and I6. One of the levers 5"! is provided at its upper end with a roller 56 rotatablymounted thereon in position to be moved toward the left in said' Fig. 1 by a cam or eccentric 68 adapted to rotate in unison with the drum H3. The mounting for the rollers 51 includes a one way clutch arrangement of any suitable type by which the rollers are permitted to rotate freely as they roll toward the right in Fig. l but are held against rotation during their movement toward the left in said figure so. as to be effective for causing the top sheet of the pile '26, to slide edgewise toward the left from the pile into the bite of the forwarding rollers 28 and 29.

. mounted by means of a shaft 62supported by frameplates 63 fixedly mounted on the standards i5 and I6. In the arrangement shown, the shaft 62 is continuously driven during the rotation of the drum by a pinion 64 on the shaft meshing with a large gear 65 carried by the drum. A cooperating stripping roller 66 is rotatably mounted between arms 61 which are fixedly mounted on a rock shaft 68- alongside of the stripping roller 6|. means being provided for rotating the shaft 68 for moving the cooperating stripping roller 66 outwardly into engagement with the inner face portion of the stripping roller 6| or for moving such roller 66 alternatively inwardly into the opening in the segmental. drum l8. The actuating means for the shaft 68 is operated in timed relation to the rotation of the drum so as to movethe roller 66 inwardly promptly after the segmental face of the drum has passed and to move such roller 66 outwardly by a quick action upon the close approach of the leading edge'of the face portion of the drum so as to enable such roller 66 to engage the free leading margin of the copy sheet extending beyond the edge of the segmental drum face.

For accomplishing these results, the rock shaft 68 is provided with a short arm 69 fixedly mounted thereon, to the outer end of which a spring i0 is connected at its upper end, the lower end of the spring being connected at H to the standard I'Bat a lower level. The arrangement is such that when the shaft 68 is rocked to the limit of its motion in counter clockwise direction in Fig. 1, the spring 10 stands at a substantial distance from the line of centers of the connection 'H and the shaft 68 so as to insure that at all times the spring 18 shall be effective for giving the shaft its required rocking movement.

Upon the shaft 68 adjacent to the short arm 6-9,

a bell crank lever 72- is mounted so' as to rotate with respect to the shaft, such bell crank lever comprising a second short arm 13 positioned adjacent to the short arm 69 and a longer arm M xtending into position to engage a cam l5 carried around by the drum I8, the arm 14 being provided with a roller [6 on its end portion for effectively engaging with the cam. For making the arm M effective for turning the shaft 68, the two short arms are connected together by a screw H which is rotatably connected with the arm 69 and adjustably connected with the arm 13. By an adjustment of the screw 11, the angular position of the arm 14 with respect to the arms 61 is controlled so as to enable the cam 15 and arm M to press the roller 66 against the roller 6! with the desired degree of pressure for making such rollers 66 and 6| effective for stripping successive copy sheets from the drum.

As will be appreciated from an inspection of Fig. 1, the stripping roller 66 when traveling outwardly toward the stripping roller 6| moves substantially tangentially of said roller Bl', as is desired for bringing about the normal delivery of the copy sheets to a tray 18. For stopping the outward movement of the arm 61 without depending too much on the engagement of the roller 66 with the roller 6!, stop plates I9 are provided adjustably mounted on the frame plates 63 with cushion members 80 of rubber or other suitable material supported thereby in position for engaging said arms 61 at the outer limits of their movement.

While the form and arrangement of parts as above described are preferred for the accomplishment of the several objects, the invention is not to be limited thereto except so far as the claims may be so limited, it being understood that changes might well be made in the construction without departing from the spirit of the invention.

I claim:

1. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, brackets mounted on said frame at one side of said drum, a platen roller, means for rotatably supporting said platen roller from said brackets so as to be movable downwardly and inwardly into engagement with the segmental face of the drum and so as to be movable additionally downwardly and inwardly when the segmental face of the drum passes beyond the platen roller, a forwarding roller rotatably mounted on said frame adjacent to said drum in position for limiting the inward and downward movement of the platen roller when the segmental face of the drum passes the platen roller, yielding means normally pressing said platen roller downwardly and inwardly to the limit of its motion, and means for moving the platen roller about said forwarding roller so as to vary the extent of inward movement of the platen roller as limited by said forwarding roller.

2. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, two arms pivotally mounted on a horizontal axis on said frame at one side of said drum, a platen roller rotatably mounted between said arms so as to be movable downwardly and inwardly into engagement with the segmental face portion of the drum, a forwarding roller rotatably mounted on said frame adjacent to said drum in spaced relation to the platen roller when supported by the drum but in position for limiting the inward and downward movement of the platen roller when the segmental face of the drum is rotated out of position for supporting the platen roller, and yielding means normally pressing said platen roller downwardly and inwardly to the limit of its motion.

3. In a duplicating machine, the combination of a, frame, a segmental drum open at a portion of its periphery and rotatably mounted on said drum, means on the drum for securing a gelatin pad thereon, brackets mounted on said frame at one side of the drum and adjustable vertically with respect to the drum, arms pivotally mounted on said brackets, a platen roller rotatably mounted between said arms so as to be movable downwardly and inwardly into engagement with the segmental face portion of the drum, a forwarding roller rotatably mounted on said frame adjacent to said drum in spaced relation to the platen roller when supported by the drum but in position for limiting the inward and downward movement of the platen roller when the segmental face of the drum is rotated out of position for supporting the platen roller, and yielding means normally pressing said platen roller downwardly and inwardly to the limit of its motion, the parts being so proportioned and positioned with respect to each other that a downward adjustment of said brackets moves the platen roller outwardly on the top face of the forwarding roller into increased spaced relation to the axis of the drum.

a. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, a platen roller rotatably mounted in position to engage the segmental face portion of the drum and movable toward and from the axis of the drum, yielding means normally holding the platen roller moved inwardly to the limit of its motion, a forwarding roller rotatably mounted adjacent to said drum below said platen roller adapted to limit the inward movement of the platen roller when the segmental face portion of the drum moves out of position for supporting the platen roller, and means active through a comparatively very small fractional portion of each revolution of the drum for starting said forwarding roller and said platen roller into cooperative rotary movement for forwarding a copy sheet shortly prior to the engagement of the platen roller with the segmental face portion of the drum.

5. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, a platen roller rotatably mounted in position to engage the segmental face portion of the drum and movable toward and from the axis of the drum, yielding means normally holding the platen roller moved inwardly to the limit of its motion, a forwarding roller rotatably mounted adjacent to said drum below said platen roller adapted to limit the inward movement of the platen roller when the segmental face portion of the drum moves out of position for supporting the platen roller, frictional driving means momentarily actuated by the rotation of the drum at a comparatively very small fract1onal portion of each revolution of the drum for starting said forwarding roller and said platen roller into cooperative rotary movement for forwarding a copy-sheet shortly prior to the engagement of the platen roller with the segmental face portion of the drum, and means for regulating the pressure of the operative parts of said frictional driving means for controlling the'slippage permitted at the start of the drive of'said rollers. Y

6. In a duplicating machine, the combination 1 of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, a platen roller rotatably mounted in position to engagethe segmental face portion of the drum and movable toward; and from the axis of the drum, yielding means normally holding the platen roller moved inwardly to thelimit' of its motion, a forwardingroller rotatably mounted adjacent to said drum below said platen roller adapted to limit the inward movement of the platen roller when the segmental, face portion of the drum moves out of position for supporting the platen roller, and frictional driving means actuated by the rotation of the drum at each revolution of the drum adapted normally to give said forwarding roller and said platen roller oooperativerotary movements at a slightly higher surface speedthan that of the drum for forwarding a copy sheet into position with'its leading edge portion extending slightly beyond the platen roller just prior to the engagement of the platen roller with the segmental face portion of the drum.

7. In a duplicating machine, the combination of a frame, a segmental drumopen at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, a platen'roller rotatably mounted in position to engage the segmental face portion of the drum and movable toward and from the axis of the drum, yielding means normally holding the platen rollermoved inwardly to the limit ofits motion, a forwarding roller rotatably mounted adjacent to said drum below said platen rolleradapted to limit the inward movement of the; platen roller when the segmental face portion of the drum moves out of position for supporting the platen roller,-a bracket pivotally mounted on said frame below said forwarding roller, a driving wheel having. a frictional facing rotatably mounted-on said bracketin position for engagement with a cooperating frictional element member carriedby the drum for rotating said driving'wheel, means for holding said bracketin adjusted position about its pivotal mounting and controlling the pressure of the driving wheel against said cooperating frictional member .on the drum, and driving connections between said driving wheel and said forwarding roller whereby at eachrevolution of the drum said forwarding roller and said platen roller are given cooperative rotary movements for forwarding a copy sheet shortly prior to the engagement of the'platen roller with the segmental face portion of the drum;

8. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mountedon said frame, meanson the drum for securing a gelatin pad thereon, a platen roller rotatably mounted in position to engage the segmental face portion of the drum and movable toward and from v the axis of the drum, yielding means normally holding the platen roller moved inwardly to the limit of its motion, a forwarding roller 'rotat I in the leading edge portion of a gelatin lyof said lugs.

'ably mounted adjacentto said drum below said platen roller adapted to limit the inward move-- ment ofthe platen roller when the segmental face portion of th'e'drum moves .out of position for supporting the platen' roller, a bracket pivotally mounted on said frame below said forwarding roller, a driving wheel having a frictional facing rotatably' mounted on said bracket in position for engagement with a cooperating frictional member carried by the drum for rotating said driving wheel, means for holding said bracket in adjustedposition about its pivotal mounting and controlling the pressure of the driving wheel against said cooperating frictional member on the drum, and pinions connecting said driving wheel with said forwarding roller adapted normallyto give said two rollers cooperative rotary 1 movements at increased surface speed as compared with that of said driving wheel for forwarding a copy sheet shortly prior to the engagement of the platen roller with the segmental face portion of the drum.

9. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted v on said frame, a plurality of lugs carried by said segmental drum at the leading edge of the face portion thereof adapted by extending loosely through openings in the leading edge portion of a gelatin pad to position the pad generally with respect to the drumindependently of the securing means for the pad, and means for holding drum and arranged so as to permit the pad to a move. freely about'the drum, and means for holding'said gelatin pad taut on said drum independently of said 1ugs.-

11. In a duplicating machine, the combination of a frame, a segmental drum-openat a portion of iits' periphery, androtatably mounted on said frame, means on the drum for securing a gelatin pad thereon, means for applying a copy sheet to the face of said gelatin pad with the leading edge portion of the copy sheet extending beyond the leading edge of the segmental face portion of the drum, a stripping roller rotatably mounted on, said frame in slightly spaced relation to the face of the drum, means for driving said stripping roller by power from said drum, a cooperating stripping roller movable into and out of engagement with the inner face portion of said firstnamed stripping roller, yielding means for moving said cooperating stripping roller inwardly away from the first named stripping roller into the opening in said segmental drum, means comprising an arm actuated by the rotation of the'drum for moving said cooperating stripping roller outwardly in timed relation to the rotation of the drum for carrying the leading edge portion of the copy sheet into pressure relationship with said first named stripping roller, and

means for adjusting the angular position of said arm with respect to said cooperating stripping roller.

12, In a duplicating machine, the combination pad thereon, means for applying a copy sheet to the face of said gelatin pad with the leading edgeportion of the copy sheet extending forwardly beyond the edge of the segmental face ,portion of the drum, a stripping roller rotatably mounted on said frame in slightly spaced relation to the face of said drum, means for driving said stripping roller by power from said drum, a rock shaft rotatably mounted adjacent to said stripping roller, two arms fixedly mounted on said rock shaft, a cooperating stripping roller rotatably mounted between said arms in position to be moved into and out of engagement with the inner face portion of said first named stripping roller, yielding means for moving said cooperating stripping roller inwardly away from the first named stripping roller into :named arm to move said cooperating stripping roller outwardly in timed relation to the rotation of the drum for carrying the leading edge portion of the copy sheet into pressure rela- Jtionship with said first named strippingroller.

13. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on v said frame, means on the drum for securing a gelatin pad thereon, means for applying a copy sheet I to the face of said gelatin pad with the leading edge portion of the copy sheet extending forward ly beyond the edge of the segmental face portion of the drum, a stripping roller rotatably mounted on said frame in slightly spaced relation to the face of said drum, means for driving said stripping roller by power from said drum, a rock shaft rotatably mounted adjacent to said stripping 'roller, two arms fixedly mounted on said rock shaft, a cooperating stripping roller rotatably mounted between said arms in position to be moved into and out of engagement with the inner face portion of said first named stripping roller, an arm swingingly mounted on said rock shaft, a short arm fixedly connected with said swingingly mounted arm, a second short arm fixedly mounted on said rock shaft adjacent to said first named short arm, means for adjusting said first named short arm angularly with respect to said second short arm, yielding means connected with one of said arms for rotating said shaft and thus moving said cooperating stripping roller inwardly away from the first named stripping roller into the opening in said segmental drum, and means comprising a cam rotatable with the drum adapted by pressure on said swingingly mounted arm to move said cooperating stripping roller outwardly in timed relation to the rotation of the drum for carrying the leading edge portion of the copy sheet into pressure relationship with said first named stripping roller;

14. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said 2,274,044 of a frame, a segmental drum open at a portion of its. periphery and rotatably mounted on said frame, means on the drum for securing a gelatin frame, means on the drum for securing a gelatin pad thereon, means for applying a copy sheet to the face of said gelatin pad with the leading edge portion of the copy sheet extending forwardly beyond the edge of the segmental face portion of the drum, a stripping roller rotatably mounted on said frame in slightly spaced rela- I tion to the face of said drum, means for driving said stripping roller by power from said drum, a rock shaft rotatably mounted adjacent to said stripping roller, two arms fixedly mounted on said rock shaft, a cooperating stripping roller rotatably mounted between said arms in position to be moved in substantially tangential direction into and out of engagement with the face of said first named stripping roller, adjustable stop means on said frame adapted by engagement with said two arms to limit the outward movement of said cooperating stripping roller, an arm swingingly mounted on said rock shaft, a short arm fixedly connected with said swingingly mounted arm, a second short arm fixedly mounted on said rock shaft adjacent to said first named short arm, means for adjusting said first named short arm angularly with respect to said second short arm, yielding means connected with one of said arms for rotating said shaft and thus moving said cooperating stripping roller inwardly away from the first named stripping roller into the opening in said segmental drum, and means comprising a cam rotatable with said drum adapted by pressure on said swingingly mounted arm to move said cooperating stripping roller outwardly in timed relation to the rotation of the drum for carrying the leading edge portion of the copy sheet into pressure relationship with said first named stripping roller.

15. In a duplicating machine, the combination of a frame, a segmental drum open at a portion of its periphery and rotatably mounted on said frame, means on the drum for securing a gelatin pad thereon, means for applying a copy sheet to the face of said gelatin pad with the leading edge portion of the copy sheet extending forwardly beyond the edge of the segmental face portion of the drum, a stripping'roller rotatabl mounted on said frame in slightly spaced relation to the face of said drum, means for driving said stripping roller by power from said drum, a rock shaft rotatably mounted adjacent to said stripping roller, two arms fixedly mounted on said rock shaft, a cooperating stripping roller rotatably mounted between said arms in position to be movable into and out of engagement with the inner face portion of said first named stripping roller, yielding means in the form of a coiled spring pivotally connected with said frame and bearing on said rock shaft at a considerable distance from the line of centers of said spring and said rock shaft effective for moving said cooperating stripping roller inwardly to the limit of its motion away from the first named stripping roller into the opening in said segmental drum, and means comprising a third arm actuated by the rotation of the drum for moving said cooperating stripping roller outwardly in timed relation to the rotation of the drum for carrying the leading edge portion of the copy sheet into pressure relationship with said first named stripping roller.

WILLIAM E. DENISON. 

